Patent GB-1502728-A (GB)
Title: Automatic turret lathes
IPC: B23Q16/00
Filed: 1976-05-18
Abstract: 1502728 Automatic turret lathes INDEXWERKE KG HAHN & TESSKY 18 May 1976 [12 June 1975] 20481/76 Heading B3T An automatic turret lathe comprises a work spindle 24 which is rotatable and axially slidable in a spindle housing 20, an indexable tool turret 38 mounted on the housing by way of a turret carriage 30 which is displaceable perpendicularly to the work spindle axis 42 the tool turret being indexable about an axis which is at an acute angle to the spindle axis and carrying tools for the external and internal machining of workplaces. In the embodiment described the spindle housing is a single unit and is constituted by the machine frame and the turret carriage is mounted symmetrically with respect to a plane containing the spindle axis 42. The work spindle 24 is contained in a bearing housing 22 and rotatable therein by a gear drive means 72, 74, 76, in a housing 78, the bearing housing 22 with the work spindle 24 being axially displaceable so as to traverse work mounted in the chuck 56 to be fed past a cutting tool 46 mounted on the tool turret to machine the external surface of the workpiece. The lathe may also be provided with a tailstock 118 which is adjustably secured on a tailstock shaft 122 which extends parallel with the work spindle and is simultaneously axially displaceable therewith to feed-traverse a workpiece mounted between centre 120 and chuck 26. The tailstock is pivotable to an inoperative position, as required, by rotation of its supporting shaft 122 by way of a friction clutch device which is operable when the tooth coupling in the drive is disengaged (Fig. 7, not shown). A drive unit 130 is provided for axially moving the spindle bearing housing 22 and tailstock supporting shaft 122. The lathe spindle 24 may also be adapted to receive barstock 88 which is fed through the spindle by way of a reciprocating gripping device 198 within the spindle which operates in conjunction with bar feed guide device 168 and the opening and closing of a collet chuck 28 actuated by a fluid operated clamping tube 162 and mounted at the fore end of the spindle, and which is related to the traversing and return motions of the spindle bearing housing and the tailstock shaft 122. To support the work piece in close proximity to the cutting tool a guide device 80 is securable to the spindle bearing housing 22 through a flange 82 and sleeve 84, the device being bell shaped and supporting the workpiece 88 coaxially with the spindle by a bush 90 at its outer end. A rough turning device 92 may also be provided and is mountable on the spindle housing 20 diametrically opposite the cutting tool in the operative position of the turret in relation to the work spindle. The device 92 comprises a tool carriage 96 transversely slidable relative to the workpiece 88 and actuated by a lever mechanism 106 which is releasbly connectible to the turret carriage 30 so as to be simultaneously movable therewith but in the opposite direction. The drive to the spindle is provided from a motor 66 via belt and gear box 68. When the lathe is operating on bar stock means is provided to stop the machine when the bar is used up. The operational sequence of the lathe may be programmed to perform a predetermined work cycle.